Mobility, diffusion and attachment of electrons in oxygen

Abstract

D/μ values (diffusion coefficient/mobility), drift velocities and attachment coefficients of electrons in oxygen have been measured over the range 5<E/p<50 V cm−1 torr−1 at 20 °C with gas pressures varying between 3 and 5 torr using a modified drift tube. For E/p>25, the measurements have also yielded values of Townsend's primary ionization coefficient. If electron detachment is neglected, the D/μ values and drift velocities are in good agreement with the available data, while the attachment coefficients differ substantially from some of the reported values. The overall accuracy of the D/μ values and the drift velocities is estimated to be better than ±3%, while the accuracy of the attachment coefficients obtained varies from ±3% for E/p<20 to about ±10% at higher E/p values.

Electron drift velocity in argon, nitrogen, hydrogen, oxygen and ammonia in strong electric fields determined from rf breakdown curves

“…From these curves we derived the electron drift velocity over the range, E/p = 69-1673 V cm −1 Torr −1 , shown in figure 7. The same figure shows the findings of papers [15][16][17][18][19][20][21]27], which are in good agreement with our results. Figure 8 presents measured breakdown curves in nitrogen for different values of the inter-electrode gap, L, and for two values of the rf field frequency: 13.56 and 27.12 MHz.…”

“…This feature is in agreement with the results obtained by Githens [22] and Chenot [23], who studied rf discharges over a broad range of rf Electron drift velocity in oxygen against E/p. The empty circles are our experimental data from turning points, the solid circles are our experimental data from minima, the solid curve presents calculated data from [15], solid triangles are for the measured data from [16], empty triangles are for the experimental data from [17], solid squares are for the experimental data from [18], empty diamonds are for the experimental data from [19], empty upside-down triangles are for the measured data from [20], empty squares are for the experimental data from [21] and solid upside-down triangles are for the measured data from [27].…”

Temporally self‐similar electron distribution functions in atmospheric breakdown: The thermal runaway regime

“…If this effect is due to a collisional detachment process as suggested by Moss et al [2006], then it must either not occur in pure O 2 ( g ) or there are differences in the timescales considered between the two experiments. In previous work we compared simulations for pure oxygen to Naidu and Prasad [1970] and found the agreement excellent. Since that work is a relatively unavailable Los Alamos National Laboratory report, we reproduce that figure here as Figure 5.…”

“…Given the difficulty in measuring accurate two‐body attachment rates and the existence of just the one experimental value, which also turns over steeply above 112 Td dropping by a factor of 2 by 137.5 Td in a manner we have never seen duplicated by simulations, we consider these values to both be in rough agreement with available measurements. This steep turn over in the two‐body attachment rate as measured by Davies [1983] is not reproduced in O 2 (g) [ Naidu and Prasad , 1970, and references therein]. If this effect is due to a collisional detachment process as suggested by Moss et al [2006], then it must either not occur in pure O 2 ( g ) or there are differences in the timescales considered between the two experiments.…”

Study of the synergistic effect in dielectric breakdown property of CO2–O2 mixtures

“…10 presents the comparison of the calculated attachment coefficient in pure O 2 with the literature data. [35][36][37][38][39][40][41][42][43][44][45] At relatively low E/N (below 20Td), a deviation between the calculated results and Grünberg's data 35 can be observed, which may be because of the adopted cross section data for the 3-body attachment. However, at relatively high E/N, the calculated data drown in the literature results.…”